—— 请按键盘 空白键 开始游戏 ——

有些人特别善于了解自己的知识极限,因为他们必须这样做。
The fundamental point in fabricating a chain reacting machine is of course to see to it that each fission produces a certain number of neutrons and some of these neutrons will again produce fission.
生活中最大的荣耀不在于从不跌倒,而在于每次跌倒后都能站起来。